oh, you're in the UK? no, I'm in the US.
they need to go into wiiu/apps/folder. the folder is already named correctly. you want the rpx or hbl version. the wii u uses rpx and elf. rpx is the main executable for games, but they're not always named the same. there's a common file that tells the system what the name of the executable is, I believe.
And just to check; I shouldn’t factory reset my console because it’ll brick…. Because my thought then would be that everything would be very cleanly installed if it was safe to do so… but it may also be completely unnecessary and not advisedyes, you'll need to buy a ds game unless you use the one already on there.